Planet Hypervisor

Training neural network using genetic algorithm

Over the last few years we observed the raise of artificially intelligent applications, which showed almost super-human ability to solve difficult problems. A closer look reveals that deep neural networks is what drives this wave.

Why open hardware must succeed

To the average person open hardware simply sounds like a good idea... They may have heard of this thing called "open source" that some "disruptive" hipster companies may have used and embraced to create new business models, so open source hardware seems like a natural progression. There's more to this though. The average person will not understand why its not just a great idea but also that we are in dire need for open hardware in the industry, the average person will not understand why its vital to the success of the open source movement. The average person will not...

XSAVE bug discovered for Skylake cpu

At first, serial console put us behind the schedule. As it was very unusual problem due to malfunctioned serial cable. And now some another bug has cost us some very precious time. The anomaly started while I was trying to boot Xen on my system, I found Xen stuck in an infinite loop of the […]

Xen and the x86 Linux zero page

This is part II, for part I - refer to "Avoiding dead code: pv_ops is not the silver bullet".On x86 Linux the boot sequence is rather complicated, so much so that it has its own dedicated boot protocol. This is documented upstream on Documentation/x86/boot.txt. The protocol tends to evolve as the x86 architecture evolves, in order to compensate for new features or extensions which could we need to learn about at boot time. Of interest to this post is the "zero page". The first step when loading a Linux kernel is to load the "zero page", this consists of a...

Avoiding dead code: pv_ops is not the silver bullet

This is part I - for part II - see "Xen and the Linux x86 zero page""Code that should not run should never run"The fact that code that should not run should never run seems like something stupid and obvious but it turns out that its actually easier said than done on very large software projects, particularly on the Linux kernel. One term for this is "dead code". The amount of dead code on Linux has increased over the years due to the desire by Linux distributions to want a single Linux kernel binary to work on different run time environments....

Linux asynchronous probe - let's try this again

Updated on 2016-01-19 with description on issue of how systemd limits the number of devices on a Linux system and references to asynchronous work on memory. Edits reflected in this color.Hipster and trendy init systems want to boot really fast. As of v4.2 the Linux kernel now sports asynchronous probe support (this fix posted December 19, 2015 is needed for use of the generic async_probe module parameter). This isn't the first time such type of work has been attempted on Linux though, this lwn article claims that a long time ago some folks tried to enable asynchronous probe and that ultimately...

Setting Devlopment Environment for Xen on Ubuntu

Development environment setup for Xen Project sounded easy to me. But it proved to be a worthy task of a standalone article. So, now I will be guiding you through the process of installing Xen Project software from source code. This article was written targeting the Xen Project 4.7-unstable on Ubuntu 15.10 (4.2.0-19-generic), but majority of […]

Kicking-off Outreachy

Finally, I got selected for Outreachy 2015. I will be working on the project “Introducing PowerClamp-like driver for Xen” with Xen Project with Dario Faggioli and George Dunlap . And this is my first blog to share my Outreachy experiences. Before jumping to my experience, I would like to mention about Outreachy. Reflective of a […]

Cambridge mini-Debconf

I am currently attending the mini-Debconf being held in space generously provided by ARM's offices in Cambridge, UK. Thanks to ARM and the other sponsors for making this possible. Yesterday I made a pass through the bug list for the Xen packages. According to the replies I have received from the BTS I looked at and acted on: #797205: Tagged to reflect that I had previously forwarded upstream. #753358: Update the found versions and marked as an upstream issue. #798510: Investigated a bit and asked some followup questions to the submitter. #799122: Asked for some clarifications from the submitter and updated the found versions. Will likely followup on this one some more today. #745419: Sent a fix to upstream. #784011,...

CodeMesh 2015

These are the slides from my talk today at CodeMesh. This time around I was earlier in the schedule so I get to enjoy the rest of the conference! If you’re reading this at the conference now, please do follow the link in my talk to rate it and give me feedback! The specific items I reference in the talk are below with links to more information. Security and the Bitcoin Piñata This is a bounty where we have locked away some bitcoin in a unikernel that is running our new TLS stack. This was a new model of running a bounty and has proven a great way...